Chinese english reading tools

Can anyone recommend a good one? I have seen the <a href="http://www.mdbg.net" target="_blank">MDBG reader</a> and <a href="http://www.cidianreader.com" target="_blank">cidianreader </a>are there any others out there to compare?

I know there are some chinese ones, what are your experiences with those? I do not want something that has a lot of ads.

一个中国人在新西兰药学英文 我想要一个中国人在新西兰为language exchange的 我学习的国语但是我说而写得不好。能个朋友在新西兰教而聊天说话 我好耐英文老师。 你也教我国语。我们一起学习帮帮向上！

我要中文老师在新西兰 可以你帮助我吗？

But: ke shi (可是) and dan shi (但是) - when to use? these words both mean "but", are there any rules when to use one or not the other? can sb explain this in English for me please?

What are some curses in 普通话? 告诉我东西不能说。。呵呵

Can: When to use neng (能), ke yi (可以), or hui (会)? Could someone please explain when to use these three different ways of expressing "can" and give me some examples. From what I can tell, these are used interchangeably, have the same meanings: "can" or "possible" or "able". What are the differences, do they imply different levels of certainty or tense, are they used in different situations, or are they just different ways of saying exactly the same thing? 谢谢!! ^_^

I want:　When to use yao 要 and when to use xiang 想？ From the way I understand it, yao is talking about a certain object ("want this"), xiang is general "i want". So I could use either when asking for a thing "wo xiang zhe" "wo yao zhe" or a drink "wo xiang he" or "wo yao he", but I could not say "wo yao qu he" (I want to go out drink), "wo yao shui jiao" (I want to sleep) or "wo yao ni" (I want you). Is this right? Could someone please explain? xiexie :) :)